Investigation of Biogas Decomposition Process for Fuel Cell Applications (PEMFC and SOFC): Thermodynamic Approach

Abstract

This paper reports a thermodynamic-based study into the production of hydrogen via biogas decomposition for use in polymer electrolyte membrane fuel cells (PEMFC) and solid oxide fuel cells (SOFC). For biogas with a CO₂/CH₄ ratio of 40 : 60, it was necessary to separate carbon dioxide before supplying the biogas to the decomposition unit to achieve higher performance. However, the decomposition of biogas with CO₂ capture under autothermal conditions was not compatible with PEMFCs because the CO concentration was higher than 10 µmol/mol. For application in SOFCs, the highest H₂ yields were achieved by combusting the methane-rich gas split from the decomposition reactor feed stream to heat the system, while those obtained by combusting the gas split from the decomposition reactor product stream resulted in the highest carbon yields and lowest overall CO₂ emissions.